Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already provide readOnlyHint and idempotentHint. The description adds valuable context: an 'honest staleness flag', cache ages, and explicit limitations on what is NOT provided (no PII, no arbitrary crawling). This goes beyond the annotations without contradicting them.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is dense and well-structured: first sentence lists the output, second confirms no args, third states scope, and fourth gives usage guidance. Every sentence earns its place, with no fluff or repetition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the zero-parameter, no-output-schema design, the description fully covers what the agent needs: what is returned (feeds, counts, new items, staleness, cache ages), scope limits, and when to use it. It is complete for a read-only health-check tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has zero parameters, so the baseline is 4. The description explicitly states 'Takes no arguments', which confirms the empty schema and removes any ambiguity for the agent. This is clear and sufficient.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('List') and a precise resource ('public disclosure feeds'), then enumerates exact output elements (cached disclosure counts, newest item, staleness flag, cache ages). This clearly distinguishes it from siblings like breach_news or breach_history, which focus on content rather than feed health.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says 'Check this first if another tool's answer looks thin', giving a concrete usage scenario. It also states scope exclusions ('no .onion access, no arbitrary fetching or crawling, no credential or PII output'), which tells when not to use the tool. This is clear when/when-not guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.